librsb 1.3.0.2

Functions
autotune.c File Reference
Example programs and code

C "RSB autotune" example program based on <rsb.h>. uses rsb_file_mtx_load(), rsb_spmm(), rsb_tune_spmm(). More...

## Functions
int | main (const int argc, char *const argv[])

## Detailed Description

C "RSB autotune" example program based on <rsb.h>. uses rsb_file_mtx_load(), rsb_spmm(), rsb_tune_spmm().

Author
  Michele Martone

/*
Copyright (C) 2008-2021 Michele Martone
This file is part of librsb.
librsb is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
librsb is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public
License along with librsb; see the file COPYING.
If not, see <http://www.gnu.org/licenses/>.
*/
/*!
\ingroup rsb_doc_examples
@file
@author Michele Martone
@brief C "RSB autotune" example program based on <rsb.h>.
uses #rsb_file_mtx_load(), rsb_spmm(), rsb_tune_spmm().
\include autotune.c
*/
#include <rsb.h> /* librsb header to include */
#include <stdio.h> /* printf() */
#include <ctype.h> /* isdigit() */
#include <stdlib.h> /* atoi() */
/* #include "rsb_internals.h" */
static int tune_from_file(char * const filename, rsb_int_t wvat)
{
struct rsb_mtx_t *mtxMp = NULL;
/* spmv specific variables */
const void * alphap = NULL; // equivalent to 1
const void * betap = NULL; // equivalent to 1
rsb_flags_t order = RSB_FLAG_WANT_COLUMN_MAJOR_ORDER;
const rsb_coo_idx_t nrhs = 2; /* number of right hand sides */
rsb_trans_t transA = RSB_TRANSPOSITION_N; /* transposition */
rsb_nnz_idx_t ldB = 0;
rsb_nnz_idx_t ldC = 0;
/* misc variables */
rsb_err_t errval = RSB_ERR_NO_ERROR;
rsb_time_t dt;
char ib[200];
const char*is = "RSB_MIF_MATRIX_INFO__TO__CHAR_P";
/* misc variables */
/* input autotuning variables */
rsb_int_t oitmax = 1 /*15*/; /* auto-tune iterations */
rsb_time_t tmax = 0.1; /* time per autotune operation */
/* output autotuning variables */
rsb_flags_t flagsA = RSB_FLAG_NOFLAGS;
/* int ione = 1; */
rsb_type_t typecodea [] = RSB_MATRIX_TYPE_CODES_ARRAY;
int typecodei;
errval = rsb_lib_init(RSB_NULL_INIT_OPTIONS);
if( (errval) != RSB_ERR_NO_ERROR )
goto err;
errval = rsb_lib_set_opt(RSB_IO_WANT_VERBOSE_TUNING, &wvat );
/*
errval = rsb_lib_set_opt(RSB_IO_WANT_EXTRA_VERBOSE_INTERFACE, &ione);
*/
if( (errval) != RSB_ERR_NO_ERROR )
goto err;
printf("Loading matrix from file \"%s\".\n",filename);
mtxMp = rsb_file_mtx_load(filename, flagsA, typecodea[0], &errval);
if( (errval) != RSB_ERR_NO_ERROR )
goto err;
for( typecodei = 0 ; typecodei < RSB_IMPLEMENTED_TYPES; ++typecodei )
{
rsb_type_t typecode = typecodea[typecodei];
struct rsb_mtx_t *mtxAp = NULL;
struct rsb_mtx_t *mtxOp = NULL;
rsb_real_t sf = 0.0;
rsb_int_t tn = 0;
sf = 0.0;
tn = 0;
printf("Considering %c clone.\n",typecode);
errval = rsb_mtx_clone(&mtxAp, typecode, transA, NULL, mtxMp,
flagsA);
if( (errval) != RSB_ERR_NO_ERROR )
goto err;
printf("Base matrix:\n");
rsb_mtx_get_info_str(mtxAp,is,ib,sizeof(ib));
printf("%s\n\n",ib);
dt = -rsb_time();
errval = rsb_tune_spmm(NULL, &sf, &tn, oitmax, tmax, transA,
alphap, mtxAp, nrhs, order, NULL, ldB, betap, NULL, ldC);
dt += rsb_time();
if(tn == 0)
printf("After %lfs, autotuning routine did not find a better"
" threads count configuration.\n",dt);
else
printf("After %lfs, thread autotuning declared speedup of %lg x,"
" when using threads count of %d.\n",dt,sf,tn);
printf("\n");
dt = -rsb_time();
mtxOp = mtxAp;
errval = rsb_tune_spmm(&mtxAp, &sf, &tn, oitmax, tmax, transA,
alphap, NULL, nrhs, order, NULL, ldB, betap, NULL, ldC);
if( (errval) != RSB_ERR_NO_ERROR )
goto err;
dt += rsb_time();
if( mtxOp == mtxAp )
{
printf("After %lfs, global autotuning found old matrix optimal,"
" with declared speedup %lg x when using %d threads\n",dt,sf,tn);
}
else
{
printf("After %lfs, global autotuning declared speedup of %lg x,"
" when using threads count of %d and a new matrix:\n",dt,sf,tn);
rsb_mtx_get_info_str(mtxAp,is,ib,sizeof(ib));
printf("%s\n",ib);
}
printf("\n");
/* user is expected to:
errval = rsb_lib_set_opt(RSB_IO_WANT_EXECUTING_THREADS,&tn);
and use mtxAp in SpMV.
*/
rsb_mtx_free(mtxAp);
mtxAp = NULL;
}
rsb_mtx_free(mtxMp);
mtxMp = NULL;
err:
rsb_perror(NULL,errval);
if ( errval != RSB_ERR_NO_ERROR )
printf("Program terminating with error.\n");
return errval;
}
int main(const int argc, char * const argv[])
{
/*!
Autotuning example.
*/
/* matrix variables */
struct rsb_mtx_t *mtxAp = NULL; /* matrix structure pointer */
const int bs = RSB_DEFAULT_BLOCKING;
rsb_coo_idx_t nrA = 500; /* number of rows */
rsb_coo_idx_t ncA = 500; /* number of cols */
const rsb_type_t typecode = RSB_NUMERICAL_TYPE_DEFAULT;
const rsb_coo_idx_t rd = 1;/* every rd rows one is non empty */
const rsb_coo_idx_t cd = 4;/* every cd cols one is non empty */
rsb_nnz_idx_t nnzA = (nrA/rd)*(ncA/cd); /* nonzeroes */
rsb_coo_idx_t*IA = NULL;
rsb_coo_idx_t*JA = NULL;
RSB_DEFAULT_TYPE*VA = NULL;
/* spmv specific variables */
const RSB_DEFAULT_TYPE alpha = 1;
const RSB_DEFAULT_TYPE beta = 1;
RSB_DEFAULT_TYPE*Cp = NULL;
RSB_DEFAULT_TYPE*Bp = NULL;
rsb_flags_t order = RSB_FLAG_WANT_COLUMN_MAJOR_ORDER;
const rsb_coo_idx_t nrhs = 2; /* number of right hand sides */
const rsb_trans_t transA = RSB_TRANSPOSITION_N;
rsb_nnz_idx_t ldB = nrA;
rsb_nnz_idx_t ldC = ncA;
/* misc variables */
rsb_err_t errval = RSB_ERR_NO_ERROR;
const size_t so = sizeof(RSB_DEFAULT_TYPE);
const size_t si = sizeof(rsb_coo_idx_t);
rsb_time_t dt,odt;
rsb_int_t t;
const rsb_int_t tt = 100; /* will repeat spmv tt times */
char ib[200];
const char*is = "RSB_MIF_MATRIX_INFO__TO__CHAR_P";
/* misc counters */
rsb_coo_idx_t ci;
rsb_coo_idx_t ri;
rsb_coo_idx_t ni;
rsb_int_t nrhsi;
/* misc variables */
rsb_time_t etime = 0.0;
/* input autotuning variables */
const rsb_int_t oitmax = 15; /* auto-tune iterations */
const rsb_time_t tmax = 0.1; /* time per autotune operation */
/* input/output autotuning variables */
rsb_int_t tn = 0; /* threads number */
/* output autotuning variables */
rsb_real_t sf = 0.0; /* speedup factor obtained from auto tuning */
const rsb_int_t wvat = 1; /* want verbose autotuning; see
documentation of RSB_IO_WANT_VERBOSE_TUNING */
if(argc > 1 && !isdigit(argv[1][0]) )
{
errval = tune_from_file(argv[1],wvat);
goto ret;
}
if(argc > 1)
{
nrA = ncA = atoi(argv[1]);
if ( nrA < RSB_MIN_MATRIX_DIM || (nrA > (RSB_MAX_MATRIX_DIM) ))
goto err;
nnzA = (nrA/rd)*(ncA/cd);
ldB = nrA;
ldC = ncA;
}
printf("Creating %d x %d matrix with %d nonzeroes.\n",(int)nrA,
(int)ncA, (int)nnzA);
IA = calloc(nnzA, si);
JA = calloc(nnzA, si);
VA = calloc(nnzA, so);
Bp = calloc(nrhs*ncA ,so);
Cp = calloc(nrhs*nrA ,so);
if( ! ( VA && IA && JA && Bp && Cp ) )
goto err;
for(nrhsi=0;nrhsi<nrhs;++nrhsi)
for(ci=0;ci<ncA/cd;++ci)
Bp[nrhsi*ldC+ci] = 1.0;
for(nrhsi=0;nrhsi<nrhs;++nrhsi)
for(ri=0;ri<nrA/rd;++ri)
Cp[nrhsi*ldC+ri] = 1.0;
ni = 0;
for(ci=0;ci<ncA/cd;++ci)
for(ri=0;ri<nrA/rd;++ri)
{
VA[ni] = nrA * ri + ci,
IA[ni] = ri;
JA[ni] = ci;
ni++;
}
if((errval = rsb_lib_init(RSB_NULL_INIT_OPTIONS))
!= RSB_ERR_NO_ERROR) goto err;
errval = rsb_lib_set_opt(RSB_IO_WANT_VERBOSE_TUNING, &wvat );
if( (errval) != RSB_ERR_NO_ERROR )
{
printf("Error setting option!\n");
goto err;
}
mtxAp = rsb_mtx_alloc_from_coo_const(
VA,IA,JA,nnzA,typecode,nrA,ncA,bs,bs,
RSB_FLAG_NOFLAGS,&errval);
/* VA, IA, JA are not necessary anymore */
free(VA);
free(IA);
free(JA);
VA = NULL;
IA = NULL;
JA = NULL;
if((!mtxAp) || (errval != RSB_ERR_NO_ERROR))
goto err;
printf("Allocated matrix of %zd nonzeroes:\n",(size_t)nnzA);
rsb_mtx_get_info_str(mtxAp,is,ib,sizeof(ib));
printf("%s\n\n",ib);
dt = - rsb_time();
for(t=0;t<tt;++t)
/*
If nrhs == 1, the following is equivalent to
rsb_spmv(transA,alphap,mtxAp,Bp,1,betap,Cp,1);
*/
rsb_spmm(transA,&alpha,mtxAp,nrhs,order,Bp,ldB,&beta,Cp,ldC);
dt += rsb_time();
odt = dt;
printf("Before auto-tuning, %d multiplications took %lfs.\n",tt,dt);
printf("Threads autotuning (may take more than %lfs)...\n",
oitmax*tmax);
dt = -rsb_time();
errval = rsb_tune_spmm(NULL, &sf, &tn, oitmax, tmax, transA,
&alpha, mtxAp, nrhs, order, Bp, ldB, &beta, Cp, ldC);
dt += rsb_time();
if(errval != RSB_ERR_NO_ERROR)
goto err;
if(tn == 0)
printf("After %lfs, autotuning routine did not find a better"
" threads count configuration.\n",dt);
else
printf("After %lfs, autotuning routine declared speedup of %lg x,"
" when using threads count of %d.\n",dt,sf,tn);
errval = rsb_lib_set_opt(RSB_IO_WANT_EXECUTING_THREADS,&tn);
if(errval != RSB_ERR_NO_ERROR)
goto err;
rsb_mtx_get_info_str(mtxAp,is,ib,sizeof(ib));
printf("%s\n",ib);
dt = -rsb_time();
for(t=0;t<tt;++t)
/*rsb_spmv(transA,&alpha,mtxAp,Bp,1,&beta,Cp,1);*/
rsb_spmm(transA,&alpha,mtxAp,nrhs,order,Bp,ldB,&beta,Cp,ldC);
dt += rsb_time();
printf("After threads auto-tuning, %d multiplications took %lfs"
" -- effective speedup of %lg x\n",tt,dt,odt/dt);
odt = dt;
tn = 0; /* this will restore default threads count */
errval = rsb_lib_set_opt(RSB_IO_WANT_EXECUTING_THREADS,&tn);
if(errval != RSB_ERR_NO_ERROR)
goto err;
errval = rsb_lib_get_opt(RSB_IO_WANT_EXECUTING_THREADS,&tn);
if(errval != RSB_ERR_NO_ERROR)
goto err;
printf("Matrix autotuning (may take more than %lfs; using %d"
" threads )...\n", oitmax*tmax, tn);
/* A negative tn will request also threads autotuning: */
/* tn = -tn; */
dt = -rsb_time();
errval = rsb_tune_spmm(&mtxAp, &sf, &tn, oitmax, tmax, transA,
&alpha, NULL, nrhs, order, Bp, ldB, &beta, Cp, ldC);
dt += rsb_time();
if(errval != RSB_ERR_NO_ERROR)
goto err;
if(tn == 0)
printf("After %lfs, autotuning routine did not find a better"
" threads count configuration.\n",dt);
else
printf("After %lfs, autotuning routine declared speedup of %lg x,"
" when using threads count of %d.\n",dt,sf,tn);
rsb_mtx_get_info_str(mtxAp,is,ib,sizeof(ib));
printf("%s\n",ib);
dt = -rsb_time();
for(t=0;t<tt;++t)
/*rsb_spmv(transA,&alpha,mtxAp,Bp,1,&beta,Cp,1);*/
rsb_spmm(transA,&alpha,mtxAp,nrhs,order,Bp,ldB,&beta,Cp,ldC);
dt += rsb_time();
printf("After threads auto-tuning, %d multiplications took %lfs"
" -- further speedup of %lg x\n",tt,dt,odt/dt);
rsb_mtx_free(mtxAp);
free(Cp);
free(Bp);
errval = rsb_lib_get_opt(RSB_IO_WANT_LIBRSB_ETIME,&etime);
if(errval == RSB_ERR_UNSUPPORTED_FEATURE)
{
printf("librsb timer-based profiling is not supported in "
"this build. If you wish to have it, re-configure librsb "
"with its support. So you can safely ignore the error you"
" might just have seen printed out on screen.\n");
errval = RSB_ERR_NO_ERROR;
}
else
if(etime) /* This will only work if enabled at configure time. */
printf("Elapsed program time is %5.2lfs\n",etime);
ret:
if((errval = rsb_lib_exit(RSB_NULL_EXIT_OPTIONS))
!=RSB_ERR_NO_ERROR)
goto err;
return EXIT_SUCCESS;
err:
rsb_perror(NULL,errval);
printf("Program terminating with error.\n");
return EXIT_FAILURE;
}

## Function Documentation

## ◆ main()

int main | ( | const int | argc,
|  | char *const | argv[]
| ) |  |

Autotuning example.